Fig. 5
Fe3+-reducing activity of the secreted proteins and low molecular weight products extracted from P. ananatis Sd-1 cultures containing rice straw on day 3 (a). Fe3+-reducing activity of pure standards of phenol, 4-hydroxy-3-methoxybenzoic acid, 4-hydroxyphenylacetic acid, propanoic acid, and phthalic acid solutions (75 µM concentration) (b). The values represent the means of the three replicates with the standard deviation (SD). Asterisks represent significant differences from secreted proteins (statistical significance: ***P < 0.001)